the group declared a terrorist organization by the obama administration. >> reporter: they're incredibly secretive. it's very difficult to actually get access to their leadership. we have been trying that. when you speak with the other fighting units, they have enormous respect for the al nusri front's capabilities because their fighters are deemed to be the most professional, the most dedicated. they're often on the deadliest and most dangerous front lines. even amongst ordinary activists who most certainly do not support al nusri's ideology, that same level of respect is echoed with people believing that, were it not for the presence of the al nusri front, they perhaps would not have been able to see the success they've seen so far in the battle for aleppo. these are the dynamic, that the country's going to have to deal with moving forward. it is important to point out, though, when it comes to the u.s. designating the al nusri front as a terrorist organization, that is not going to change the battlefield dynamicings in syria. the opposition activist, the free syrian army, do not feel